Electrical switching means



H. J. MCCARTHY I 2,382,646

ELECTRICAL SWITCHING MEANS Filed March 13, 1942 Fig. 5 7

H en1 H J. M0 Ca 1 thHJNVENTOR.

BY M

ATT ORNEY Patented Aug. 14, 1945 UNITED STATES PATENT OFFICE 2,382,0 6ELECTRICAL SWITCHING MEANS,

Henry J. McCarthy, Danvers, Masa, assignor to Sylvanla Electric ProductsInc., a corporation of Massachusetts Application March 13, 1942, SerialNo. 434,627

' 1 Claim.

The present invention relates to portable electric illuminating devices.It relates more specifically to means for controlling and limiting theirshown inFigure 1, the cutout l is placed in the socket 4 between thebulb 2 and the terminal 3.

The cutout I, shown in section, is comprised of the 'drive screw contact5, the metal plug contact 8 and th insulator l. Enclosed in the chamberformed by the plug and the insulator'is a drop of mercury 8. The size ofthis drop of mercury; the

' length of the drive screw, and the angular disgerous and unlawful tohave a source of light that can be seen above the horizontal. However,in such times of stress it is entirely possible that one mightunintentionally shine a light upwards, particularly in the case ofrescue workers who must both carry on their work and provide their ownlight. Furthermore a dropped light might con tinue to burn in a verticalposition. Various systems of masking and dimming flashlights have beenemployed to minimize the danger of showing excessive light. There hasnot been any means thus far devised which will keep the light fromshining when a flashlight isso disposed that the lens is directedupwardly. Therefore, an object or my invention is to provide-a practicalmeans for breaking the electrical circuit between the light and itspower source, thereby xtinguishing the light when said light is handledin such manner as to expose direct rays so that they may be seen fromabove. Another object of my invention is to have the switching meansautomatic so that it is completely. foolproof. An advantage of myinvention is that it is extremely compact, adding no bulkinesswhatsoever to the device. Further it may be incorporated into anyportable illuminating device commonly in use. This may be done simply,by anyone, as it does not require technical knowledge to install.Finally, it may be made and sold economically. Still other objects andadvantages will be apparent from the following specification taken inconjunction with the accompanying drawing in which:

Figure 1 is a side elevation partly in section of the bulb socket of anordinary flashlight and the cutout oi. my invention incorporatedtherein.

Figure 2 is a cross sectional view of a modification of said cutout. 1

Figure 3 is a perspective'oi said cutout- My invention may be employedby removing the bulb from any flashlight, inserting the cutout into thebulb holder, and replacing said bulb. As

position of the portion of the chamber wall formed by the insulatingmember determine the angle at which the cutout will break the circuit bymeans of the mercury 8 rolling away from the drive screw 5 breaking thecontact between contact 5 and the plug 8. Since a flashlight bulb givesonly a feeble glow unless directionalized by means of a reflector andlens, it is reasonable to consider the direction or its light outputsynonymous with its longitudinal axis so that the beam 0! light will beprojected in the same direction as the angle or plane which thelongitudinal axis assumes.

In Figure 3, the cutout I is shown in perspective,

element 5 being the head of the drive screw and element 6 the metal plugcontact.

In Figure 2, the plug 6 and the drive screw 5 are altered to accommodatea substitution of material used for element 8. As above disclosed saidelement 8 is a drop of mercury. However, it may be found desirable tosubstitute a silver-plated ball. In such a case element 6 would have alipon its edge which would also be silver-plated. This structure, inconjunction with a beveled edge on element 5, would tend to improve thecontact through element 8. In such a case the angle at which the cutoutwould take effect is controlled by the pitch of the lip of element 8.

What I claim is:

In combination with a socket and an electric lamp having a sleeve-likeouter contact member and an axial inner contact member, a control unitdetachably received in said socket comprising a cylindrical body memberof insulating material having arecess in each end connected by an axialaperture, the recess adjacent the lamp being of inwardly convergentconical form, a conductor extending into said other recess into closeproximity to said conductor, and a mobile body of conductive materialwithin said cup shaped contact of sufllcfent size to bridge the spacebetween said contact and said conductor when said unit is in aparticularrange of positions.

. HENRY J. MoCARTHY.

